Each fall we have the honor of sharing the Kezar Outlet Fen with a group of 30+/- students and their teachers from Molly Ockett Middle School’s Maine Environmental Science Academy (MESA). MESA is an interdisciplinary, experiential place-based program for 6th - 8th graders.
This year, given the current pandemic, we weren’t sure if the field trip would take place, but the teachers reached out to us a couple of weeks ago and said that if we could offer two trips, one each for 15 students on consecutive days, they’d greatly appreciate it. They also mentioned that earth science is their focus for this year with soil science being a part of that study.
Bingo. The fen is ideal for such. And so, upon their arrival, we marched in and stopped at a kettle hole where we talked briefly about the services of wetland soils: water purification, wildlife habitat, and flood control; and then began to discuss three characteristics of a wetland, the first being saturation.
Saturation: Wetlands are . . . wet. Saturated. But . . . that comes in different forms. There are vernal pools that fill with water and dry up; rivers, lakes, and ponds like Saco River, Kezar Lake, and Lovewell Pond that are saturated more permanently; and . . . other wetlands that are groundwater dependent, such as the kettle. A kettle is a depression created by an ice block that fell out of a receding glacier, which dips into underground stores of water, thus making it less sensitive to drought.
And the soils in a wetland? Hydric. They lack oxygen due to permanent or seasonal saturation. We had a jar of garden soil to show and it was obvious that it was of dry consistency with pores between the soil particles that allow air to move.
When soil is flooded, however, water fills those pores and prevents the flow of air, thus creating a lack of oxygen called anaerobic conditions. This influences processes that can take place in the hydric soils.
Most decomposers such as microorganisms and earthworms require oxygen. With slowed decomposition of organic matter, the result is enrichment of wetland soil. In it, organic matter builds up rather than decays, and it is consequently dark colored. (I might have mentioned that likewise, when a mammal eats a prey species, it often digests the organic matter first and the result is a dark organ-filled scat.)
The third characteristic of a wetland is Hydrophytic Plants. These are water-loving plants, or as we say, they love wet feet.
We know that the green parts of plants take in carbon dioxide and produce the oxygen we breathe. Plant roots also require oxygen for respiration (the process of taking in oxygen and producing energy).
Hydrophytic plants, however, can’t do that in the same manner and so they are specially adapted to grow in saturated soils with low oxygen. Some, like cattails, have special chambers in their roots that allow air to flow.
Others, like Pitcher Plants that we would see before the field trips ended, and other carnivorous plants thrive in nutrient poor soils of bogs and fens by trapping insects and digesting essential nutrients such as nitrogen, calcium, magnesium, and potassium. As I explained with my sketch, the plants lips eventually turn ruby-red and remind me of my home economic’s teacher when I was in middle school. Wait, I didn’t go to middle school. I attended junior high. And home economics no longer exists. Anyway, we gals had to take that course and learn to sew and cook (two of my least favorite activities to this day) while the boys took wood shop. Our teacher, Mrs. Jennings, wore bright red lipstick, so much so that I always secretly called her Mrs. Ruby Lips. And the red lips we’d see later on the living plants reminded me of Mrs. Ruby Lips.
Insects are enticed by the red plus nectar glands and the brightly colored veins that remind me of a Tree of life. Life for the plant that is. Not necessarily so for the insect. Once enticed, the insect follows downward pointing hairs into the trap and can’t climb out. Below the hairs, it reaches a smooth zone where it encounters sticky goo, further impeding its attempts to escape. Eventually it drowns in rainwater that fills the pitcher leaf and is digested by bacteria and enzymes the plant releases into the water. Nutrients stated above are then absorbed by the plant.
Here’s another cool fact: Some insects have anti-enzymes that counteract the digestive enzymes in the fluid. And they feed on the remains of the decomposed insects. Nothing goes to waste.
Phew. That was a lot of information to absorb in a few minutes. But, the cool thing about this group of students is that their teachers and their older peers teach them how to learn. And so they broke into study groups consisting of students from all three grades and reviewed their notes to make sure they all were on the same page.
Reflection, critical analysis, and synthesis are part of their program.
When we circled up again, we had a brief overview of layers within wetland soils. The organic wetland soils with noticeable amounts of partially decomposed plants due to that lack of oxygen we’d mentioned earlier, look like black muck or brown/black peat.
Below them are the mineral soils formed over time from the weathering of rocks. They have little or no organic material and what one typically finds is sand, silt, and/or clay. Mottled soil experiences both wet and dry conditions. It may include splotches of iron or manganese. When dry, air does move through this layer, the mineral concentrations oxidize. As a result, the iron rusts, leaving behind shades of red, orange, and yellow. Manganzes mottles are typically black.
Gleyed (pronounced “glade”). soils are saturated all the time, and therefore anaerobic. This layer tends to be gray, greenish, or bluish gray.
Again, that was a lot of info to share, and this is an experiential class, so it was time to get down and dirty and see if what was below our feet matched the information they’d jotted down. Each day, the fifteen students were divided into three groups of five who worked together. One group was assigned a spot closer to the center of the kettle to dig a hole about two feet deep. They were instructed to be extra careful when pulling up the organic layer because in the end, everything needed to go back into the holes and the top layer would be tapped down so that it sorta looked like we’d never touched it. We very much embrace the Leave No Trace philosophy as much as possible.
A second group was assigned a spot on the edge of the vegetation that grew around the kettle.
And a third group dug in a much more vegetated area.
That was on Thursday morning. On Friday morning, we visited a kettle hole located just north of the first one and again, one group dug toward the center. I say “toward the center” because on Saturday during a pre-hike, I noted water there. It wasn’t present on Friday, but the muck was . . . super mucky.
Again, a second hole was dug toward the edge of the kettle.
The third hole on the second day was in a much more vegetated area than any of the others had been so it was helpful that one of the students used a trowel to break through the roots.
Two things to note: 1. After circling up by their bus which was parked about a quarter mile from the wetland, each student was given a tool or field guide to carry. No one complained. No one misplaced anything.
2. Notice the green vegetation. We are still experiencing drought conditions in western Maine and much of the vegetation has browned and dried up. But, we were on the outskirts of a kettle hole that was fed by groundwater.
Once the holes were dug, we asked the kids to assess them based on the chart. They noted the various soils,
measured the organic layer of their hole and their classmates’ holes,
felt the texture and tried to create shapes out of the clay,
and gave thanks they were wearing masks because especially the holes toward the center of the depression smelled like a stinky harbor at low tide.
At last it was time for us to leave behind the kettle holes, (after filling in the student-made holes, of course), but first we noted the wildlife that call this place home. Between the two small kettle holes we explored over the two days, the raccoons had left their baby hand prints and everyone noted it was a well-traveled highway. We also measured the stride of a moose, and spotted deer prints in the mix. Plus birds. These kids are excellent birders and know to stop the group anytime they spy or hear one. We like that cuze it’s what we know as Nature Distraction Disorder. There’s nothing better than being distracted by nature.
After making sure we had everything, we made our way into the wetland jungle with the destination of the cranberry fen in our minds.
Winterberry and Buttonbush, among other shrubs, channeled their inner Hobblebush and caused us to get trapped and entangled time and time again.
Arriving at the fen with no complaints from anyone, GLLT’s Executive Director Erika Rowland, who was able to join us for Thursday’s trip, shared information about Paleoecology, telling the kids that people take core samples and study ancient organisms and how they interact with the environment and one another. She explained that we were standing in a peatland, which could provide a treasure trove of information about what the landscape looked like vegetation-wise hundreds to thousands of years ago.
Rather than dig three holes, only one was excavated each day, and really it was more difficult to break through the peat.
It consisted of layers upon layers of sphagnum and other plants.
Had we had a top-notch microscope, we might have been able to view pollen, but for the sake of illustration, Erika shared macro-photos of pollen from species such as alder, birch, and pine.
And then it was time for the kids to go on a treasure hunt of their own making. The gems they sought were located at their feet and dangled like Christmas bulbs from stems with alternate leaves that were leathery and green above and dull white on the underside.
Every year my mind is blown away by how much the kids love to forage for cranberries.
And find wonder in the experience.
Though it isn’t a competition, they try to fill their bags completely and talk about recipes and holiday traditions as they pick.
Several were even overhead saying how much they loved it in the fen and could easily live there.
As promised before it was time to leave, we took them to a spot where at least three large Pitcher Plants grow.
Two were more hidden from the sun and didn’t show off as much red coloration.
We chatted with the kids again about the adaptations of the plant and encouraged them to stick a finger down into the pitcher-shaped leaf.
They survived the experience and weren’t eaten by the plant, thankfully ;-) But they did feel the texture of the hairs, located the smooth zone, and touched the water. A few even saw some insect body parts.
Oh, and there were other discoveries to be made, like watching grasshoppers and spiders and even a wee meadowhawk dragonfly, discovering vole holes and pathways, and finding a shed snake skin.
Thanks to Mr. Oliver, their English/Language Arts teacher, Mrs. Lewey, their science teacher, and Mrs. Barry, their math teacher who stayed behind both days with the other 15 students . . .
And thanks to our very own former GLLT intern, Audra, who was once a MESA student, and is now a freshman at Mount Holyoke College remotely by night, and known as Miss Hamlin by day because . . . she has been hired to help with the program.
We’re so glad that the four of you have figured out a way to make these field trips work and hope that we can continue to offer you more opportunities to explore on our properties.
We especially thank the thirty students who applied to get into this program and know the value and fun of getting their hands dirty.
As Mr. Oliver reminded them all at the end of Friday’s trip, “This is your classroom.”
Indeed.